Embodiments of this disclosure relate generally to power converters, and more particularly, to an Alternating Current (AC) to AC power converter that does not require a Direct Current (DC) link or storage devices.
Wind turbines and flywheels are types of renewable energy devices that output variable frequency, variable voltage, AC electric power. Therefore, power converters may be used to convert the variable-frequency, variable-voltage, AC electric power to fixed-frequency, fixed-voltage, AC power.
Wind turbine power systems spend a lot of time operating at light loads or fractions of their rated power capacities. These variable frequency drives typically employ dc voltage or current links for power distribution between the input and output converters and as a means to temporarily store energy. Thus, conventional power converters convert the generated AC power to DC power then to the required AC power. Unfortunately, this method renders a low yield conversion. Standard, state-of-the-art, power converters are designed to operate most efficiently at full power all, or nearly all, of the time. Therefore, when wind turbine-driven generators are operating in low wind, light load, conditions, standard power converters are inefficient.
Therefore, it would be desirable to provide a system and method that overcomes the above problems.